This invention relates generally to refrigeration devices, and more particularly, to control systems for refrigerators.
Current appliance revitalization efforts require electronic subsystems to operate different appliance platforms. For example, known household refrigerators include side-by-side single and double fresh food and freezer compartments, top mount, and bottom mount type refrigerators. A different control system is used in each refrigerator type. For example, a control system for a side-by-side refrigerator-controls the freezer temperature by controlling operation of a mullion damper. Such refrigerators may also include a fresh food fan and a variable or multi-speed fan-speed evaporator fan. Top mount refrigerators and bottom mount refrigerators are available with and without a mullion damper, the absence or presence of which affects the refrigerator controls. Therefore, control of the freezer temperature in top and bottom mount type refrigerators is not via control of a mullion damper. In addition, each type of refrigerator, i.e., side-by-side, top mount, and bottom mount, have different optimal control algorithms for most efficiently controlling refrigerator operation. Conventionally, different control systems have been employed to control different refrigerator platforms, which is undesirable from a manufacturing and service perspective. Accordingly, it would be desirable to provide a configurable control system to control various appliance platforms, such as side-by-side, top mount, and bottom mount refrigerators.
In addition, typical refrigerators require extended periods of time to cool food and beverages placed therein. For example, it typically takes about 4 hours to cool a six pack of soda to a refreshing temperature of about 45xc2x0 F. or less. Beverages, such as soda, are often desired to be chilled in much less time than several hours. Thus, occasionally these items are placed in a freezer compartment for rapid cooling. If not closely monitored, the items will freeze and possibly break the packaging enclosing the item and creating a mess in the freezer compartment.
Numerous quick chill and super cool compartments located in refrigerator fresh food storage compartments and freezer compartments have been proposed to more rapidly chill and/or maintain food and beverage items at desired controlled temperatures for long term storage. See, for example, U.S. Pat. Nos. 3,747,361, 4,358,932, 4,368,622, and 4,732,009. These compartments, however, undesirably reduce refrigerator compartment space, are difficult to clean and service, and have not proven capable of efficiently chilling foods and beverages in a desirable time frame, such, as for example, one half hour or less to chill a six pack of soda to a refreshing temperature. Furthermore, food or beverage items placed in chill compartments located in the freezer compartment are susceptible to undesirable freezing if not promptly removed by the user.
Attempts have also been made to provide thawing compartments located in a refrigerator fresh food storage compartment to thaw frozen foods. See, for example, U.S. Pat. No. 4,385,075. However, known thawing compartments also undesirably reduce refrigerator compartment space and are vulnerable to spoilage of food due to excessive temperatures in the compartments.
Accordingly, it would further be desirable to provide a quick chill and thawing system for use in a fresh food storage compartment that rapidly chills food and beverage items without freezing them, that timely thaws frozen items within the refrigeration compartment at controlled temperature levels to avoid spoilage of food, and that occupies a reduced amount of space in the refrigerator compartment.
In order to provide a quick chill and thawing system it would be desirable to have an electronic controller that controls the operation of the refrigerator and controls the operations of the quick chill thaw compartments.
In an exemplary embodiment, an electronic control system is provided for a refrigeration system including at least one refrigeration compartment and a quick chill/thaw pan located in the refrigeration compartment. The control system includes a main controller board, a temperature adjustment board, a dispenser board, and a serial communications bus. The main controller board is electrically connected to the temperature adjustment board and the dispenser board through the serial communications bus for controlling the temperature of the refrigeration compartment and the quick chill/thaw pan. The control system transmits commands over the serial communications bus to the dispenser board and the temperature adjustment board. The control system accepts a plurality of inputs including a refrigeration compartment temperature and a quick chill/thaw mode, determines a state of the refrigeration system, transmits commands over the serial communications bus, and executes a plurality of algorithms to control the refrigeration compartment and the quick chill/thaw pan over the serial communications bus.
The control system further includes a human machine interface board operatively coupled to the main controller board for user manipulation to select features of the refrigeration system, such as operation mode of the quick chill/thaw pan, to input user-selected operating setpoints such, as for example, a desired refrigeration compartment temperature, and to display actual temperature conditions and selected features of the refrigerator system.
The control system is configured to acquire status information from a variety of refrigeration components to make control decisions, included but not limited to status of a fresh food fan, a condenser fan, an evaporator fan, a quick chill/thaw pan fan, a compressor, a heater, an alarm, a cradle, various timers, and refrigeration compartment opened or closed door conditions. Based upon the status of the refrigeration system, the control system operates the refrigeration components according to a plurality of modes, e.g., an initialize mode, a prechill mode, a normal cooling mode, an abnormal cooling mode, a defrost mode, a diagnostic mode, and a dispense mode. A plurality of software algorithms are executed by the control system for the applicable modes, including but are not limited to a sealed system algorithm, a sensor-read-and-rolling-average algorithm, and a defrost algorithm.
The sealed system algorithm controls operation of a defrost heater, an evaporator fan, a compressor, and a condenser fan; a fresh food fan algorithm to control operation of a fresh food fan based on door opened and closed conditions. The sensor-read-and-rolling-average algorithm is used calibrate various thermistors and sensors and store associated data to accurately determine operating conditions of the refrigeration system. Additional control algorithms are executed to control the operation of resetting a water filter, dispensing water from the refrigeration system, dispensing crushed ice, dispensing cubed ice, activating and deactivating a light, and locking a dispenser keypad interface.